The major function of absorbent articles such as disposable diapers and incontinent briefs or undergarments is to absorb and contain body exudates. Such articles are thus intended to prevent body exudates from soiling, wetting, or otherwise contaminating clothing or other articles, such as bedding, that come in contact with the wearer. The most common mode of failure for such products occurs when body exudates leak out of the gaps between the article and the wearer's leg or waist to adjacent clothing because they are not immediately absorbed within the article and the absorbent article is not able to sustain a good fit on the wearer such that gaps are created allowing the exudates to leak out of the chassis of the absorbent article. For example, urine tends to be deposited into the topsheet in gushes such that the urine migrates to the gaps in the chassis where it can come in contact with clothing or other articles and be absorbed by these articles. Additionally, loose fecal material that is not easily absorbed by the absorbent article tends to "float" on the liquid-receiving surface and work its way past the gaps in the article in the legs or waist of the wearer.
Contemporary disposable diapers have a topsheet, a backsheet, an absorbent core, and elasticized leg flaps generally formed from an elastic member being enclosed in the continuous topsheet and backsheet which extend beyond the edges of the absorbent core. These elasticized leg flaps prove effective generally to prevent wicking and overflow from the fluid laden diaper to clothing contacting the edges of the diaper in that the elasticized leg flaps present a fluid impervious barrier between the edge of the diaper and the contacting clothing, and in addition, provide a gasketing action about the legs of the wearer to maintain a seal about the leg and minimize gapping. However leakage along the perimeter of the diaper may still occur. As the diaper is worn for longer periods of time, forces tend to act on the diaper to degrade the initial fit on the wearer. Large gaps and sagging of the diaper in the legs and waist are formed by the degradation in fit. Thus, as liquids are deposited onto the topsheet, some of the liquid is not immediately absorbed through the topsheet and migrates toward the edges of the diaper where it can leak through or past the gaps in the diaper and come in contact with clothing or undergarments where it can be absorbed by and wicked into such garments.
Disposable diapers may be provided with barrier cuffs which inhibit loose fecal material or gushes of urine or liquids from soiling the wearer's clothing. The barrier cuffs restrain the free flow of this material and provide a structure to hold such material within the diaper so that as such material freely floats or flows on the topsheet of the diaper, it is contained within the diaper. Despite the effectiveness of such structures in containing such material, it has been found that liquids can leak through the barrier cuffs and soil the weareres clothing. In addition, the barrier leg cuffs can cause skin marking in the area where the leg cuff contacts the skin.
It has now been discovered that applying a lotion coating on the surface of the leg cuffs that is transferable to the wearer's skin by normal contact and wearer motion and/or body heat can improve the containment characteristics, reduce skin irritation, of the diaper as well as lead to improved ease of BM clean up. As used herein, the term leg cuff includes barrier leg cuffs, gasket cuffs and combinations and variations thereof. The coating of the cuffs with the lotions disclosed herein can increase the hydrophobicity of the cuffs, thereby improving the leakage performance. The hydrophobic lotion coating allows for flexibility in cuff designs using nonwoven materials by providing an alternate method to achieve the desired hydrophobicity. This can lead to reduced material costs. Importantly, the lotions disclosed in the present invention act to minimize the abrasion between the cuffs and skin in the area where the cuffs contact the wearer's skin, resulting in less skin irritation. The lotions also provide a protective coating on the wearer's skin that helps prevent the adherence of BM to the skin, thereby improving the ease of BM cleanup.
One substance that has been applied as a lotion to diaper products to impart a soothing, protective coating is mineral oil. Mineral oil (also known as liquid petrolatum) is a mixture of various liquid hydrocarbons obtained by distilling the high-boiling (i.e., 300.degree.-390.degree. C.) fractions in petroleum. Mineral oil is liquid at ambient temperatures, e.g. 20.degree.-25.degree. C. As a result, mineral oil is relatively fluid and mobile when applied to diapers. Because mineral oil is fluid and mobile at ambient temperatures, it tends not to remain localized on the body contacting surface of the barrier leg cuffs, but instead migrates through the leg cuffs into the interior of the diaper. Accordingly, relatively high levels of mineral oil need to be applied to the barrier leg cuffs to provide the desired therapeutic or protective coating lotion benefits. This leads not only to increased costs for these lotioned barrier leg cuff diaper products, but other detrimental effects as well, including decreased absorbency of the underlying absorbent core.
Even without increasing its level, the tendency of mineral oil to migrate once applied has other detrimental effects. For example, the applied mineral oil can transfer to, into and through the packaging or wrapper material for the lotioned diaper product. This can create the need for barrier-type packaging or wrapper films to avoid smearing or other leakage of mineral oil from the diaper product.
Accordingly, it would be desirable to provide diaper products having lotioned leg cuffs that: (1) have desirable therapeutic or protective coating lotion benefits (2) do not require relatively high levels of coatings that are liquid at room temperature (e.g., mineral oil) (3) do not adversely affect the absorbency of the diaper product; and (4) do not require special wrapping or barrier materials for packaging.
Therefore, it is an object of the present invention to provide a diaper having lotioned leg cuffs wherein the lotion is transferable to the wearer's skin and provides desirable therapeutic benefits, resulting in less skin irritation.
It is a further object of the present invention to provide a diaper having lotioned leg cuffs wherein the lotion is transferable to the wearer's skin and is effective at reducing the adherence of BM to the skin, thereby improving the ease of BM cleanup.
It is a further object of the present invention to provide a disposable diaper having leg cuffs having improved liquid containment properties.
It is yet a further object of the present invention desirable to provide diapers having lotioned leg cuffs that do not require relatively high levels of mineral oil, and do not require special wrapping or barrier materials for packaging.
These and other objects are obtained using the present invention, as will become readily apparent from a reading of the following disclosure.